Syntho-Glass® NP

Syntho-Glass® NP Repair System was specifically designed for depressurized pipe repair applications on copper, steel, SS, PVC, FRP, clay, concrete, rubber, and more.

By combining the original Syntho-Glass® product, with the extremely chemically resistant Syntho-Steel™, this offers the geometric flexibility to repair joints, tees, couplings, and pinholes. This complete system simplifies the application process and is prepackaged to accommodate pipes up to 10 inches in diameter. Larger repair applications can be engineered to meet your requirements.



DatasheetSDS Sheet
InformationTesting Data
Typical Applications

  • Depressurized leak repair on:
    • Joints
    • Pinhole
    • Cracks


  • Ready to use
  • Heat resistant
  • Effective, time-saving
  • No mixing and no mess
  • Sets rock hard in minutes
  • NSF61 and BS6920 approved for potable water when Syntho-Steel is used as the primary sealant


Application temperature: 32 to 150°F (0° to 65°C)

Related Products

  • Syntho-Steel Putty
  • Syntho-Glass
  • Butyl Tape

Surface Preparation

Surface preparation and profiling shall promote continuous intimate contact between the FRP system and pipe by providing a clean, smooth, and circumferential surface. Surface preparation shall be in accordance with SSPC-SP1 “Solvent Cleaning” and SSPC-SP11 “Power Tool Cleaning” with a 1-3 mil surface roughness (25-75 microns) minimum. If an existing coating is present, roughen to degloss. NRI’s composite repair systems are bond-critical and require a strong adhesive bond between the clean pipe and the composite system. Test Method Result Tensile Strength ASTM D638 36,000 psi (2,482.1 bar) Lap Shear Strength ASTM D5379 900 psi (62.05 bar) Flexural Strength ASTM D790 26,100 psi (1,799.53 bar) Dielectric Strength ASTM D149 16,000 Volts.


Installation of the Syntho-Glass NP composite repair system shall be performed by NRI qualified applicators only. Surface preparation, mixing of epoxy, material saturation, and installation of the system shall be in accordance with NRI’s product specific installation guides, latest revision. Quality control inspection during and after installation of the system shall be performed per NRI’s Installation Validation Procedure: Quality Control Records, latest revision.

Mechanical Properties

Tensile StrengthASTM D63836,000 psi (2482.1 bar)
Lap Shear StrengthASTM D5379900 psi (62.05 bar)
Flexural StrengthASTM D79026,100 psi (1799.53 bar)
Dielectric StrengthASTM D14916,000 Volts